Optimized add_int64 and sub_int64. Previous commit was done by mistake during WIP.

1 files changed, 12 insertions, 119 deletions

diff --git a/main.c b/main.c
index 628bb94..5ddbf08 100644
--- a/main.c
+++ b/main.c
@@ -220,23 +220,21 @@ char *sprint_time5_utf8(char *string, intmax_t time, int space) {
 }
 
 int64_t add_int64(int64_t x, int64_t y) {
-	if (y > 0 && x > INT64_MAX - y)
-		return INT64_MAX;
-	
-	if (y < 0 && x < INT64_MIN - y)
-		return INT64_MIN;
-	
-	return x + y;
+	int64_t result;
+	bool overflow = __builtin_add_overflow(x, y, &result);
+	if (overflow) {
+		result = ((uint64_t)x >> 63) + INT64_MAX; // Equivalent to (x > 0 ? INT64_MAX : INT64_MIN)
+	}
+	return result;
 }
 
 int64_t sub_int64(int64_t x, int64_t y) {
-	if (y < 0 && x > INT64_MAX + y)
-		return INT64_MAX;
-	
-	if (y > 0 && x < INT64_MIN + y)
-		return INT64_MIN;
-	
-	return x - y;
+	int64_t result;
+	bool overflow = __builtin_sub_overflow(x, y, &result);
+	if (overflow) {
+		result = ((uint64_t)x >> 63) + INT64_MAX; // Equivalent to (x > 0 ? INT64_MAX : INT64_MIN)
+	}
+	return result;
 }
 
 // Returns active task or NULL if none applies.
@@ -460,57 +458,10 @@ void update_times(database_st *db) {
 	}
 }
 
-int64_t super_add(int64_t x, int64_t y) {
-	int64_t result;
-	if (__builtin_add_overflow(x, y, &result)) {
-		result = (x > 0 ? INT64_MAX : INT64_MIN);
-// 		result = (x >> 63) ^ INT64_MAX;
-// 		result = ((uint64_t)x >> 63) + INT64_MAX;
-	}
-	return result;
-}
-
 // Recalculates database totals.
 void update_total_times(database_st *db) {
 	assert(db != NULL);
 	
-	/*
-	// 100 MOPS
-	int64_t *total_times = db->total_times;
-	memset(db->total_times, 0, NUM_WEEK_DAYS * SIZEOF_INT64);
-	for (size_t idx = 0; idx < db->count; idx++) {
-		int64_t *times = db->tasks[idx].times;
-		for (int it = 0; it < NUM_WEEK_DAYS; it++) {
-			total_times[it] = add_int64(total_times[it], times[it]);
-		}
-	}
-	*/
-	
-	/*
-	// 120 MOPS
-	int64_t *d0 = &db->total_times[0];
-	int64_t *d1 = &db->total_times[1];
-	int64_t *d2 = &db->total_times[2];
-	int64_t *d3 = &db->total_times[3];
-	int64_t *d4 = &db->total_times[4];
-	int64_t *d5 = &db->total_times[5];
-	int64_t *d6 = &db->total_times[6];
-	memset(db->total_times, 0, NUM_WEEK_DAYS * SIZEOF_INT64);
-	
-	for (size_t idx = 0; idx < db->count; idx++) {
-		int64_t *times = db->tasks[idx].times;
-		*d0 = add_int64(*d0, times[0]);
-		*d1 = add_int64(*d1, times[1]);
-		*d2 = add_int64(*d2, times[2]);
-		*d3 = add_int64(*d3, times[3]);
-		*d4 = add_int64(*d4, times[4]);
-		*d5 = add_int64(*d5, times[5]);
-		*d6 = add_int64(*d6, times[6]);
-	}
-	*/
-	
-	/*
-	// 122 MOPS
 	memset(db->total_times, 0, NUM_WEEK_DAYS * SIZEOF_INT64);
 	for (size_t idx = 0; idx < db->count; idx++) {
 		int64_t *times = db->tasks[idx].times;
@@ -522,51 +473,6 @@ void update_total_times(database_st *db) {
 		db->total_times[5] = add_int64(db->total_times[5], times[5]);
 		db->total_times[6] = add_int64(db->total_times[6], times[6]);
 	}
-	*/
-	
-	/*
-	// 140 MOPS
-	memset(db->total_times, 0, NUM_WEEK_DAYS * SIZEOF_INT64);
-	for (size_t idx = 0; idx < db->count; idx++) {
-		int64_t *times = db->tasks[idx].times;
-		__builtin_add_overflow(db->total_times[0], times[0], &db->total_times[0]);
-		__builtin_add_overflow(db->total_times[1], times[1], &db->total_times[1]);
-		__builtin_add_overflow(db->total_times[2], times[2], &db->total_times[2]);
-		__builtin_add_overflow(db->total_times[3], times[3], &db->total_times[3]);
-		__builtin_add_overflow(db->total_times[4], times[4], &db->total_times[4]);
-		__builtin_add_overflow(db->total_times[5], times[5], &db->total_times[5]);
-		__builtin_add_overflow(db->total_times[6], times[6], &db->total_times[6]);
-	}
-	*/
-	
-	// 140 MOPS
-	memset(db->total_times, 0, NUM_WEEK_DAYS * SIZEOF_INT64);
-	for (size_t idx = 0; idx < db->count; idx++) {
-		int64_t *times = db->tasks[idx].times;
-		db->total_times[0] = super_add(db->total_times[0], times[0]);
-		db->total_times[1] = super_add(db->total_times[1], times[1]);
-		db->total_times[2] = super_add(db->total_times[2], times[2]);
-		db->total_times[3] = super_add(db->total_times[3], times[3]);
-		db->total_times[4] = super_add(db->total_times[4], times[4]);
-		db->total_times[5] = super_add(db->total_times[5], times[5]);
-		db->total_times[6] = super_add(db->total_times[6], times[6]);
-	}
-	
-	/*
-	// 110 MOPS
-	memset(db->total_times, 0, NUM_WEEK_DAYS * SIZEOF_INT64);
-	int64_t *totals = db->total_times;
-	for (size_t idx = 0; idx < db->count; idx++) {
-		const int64_t *restrict times = db->tasks[idx].times;
-		totals[0] = add_int64(totals[0], times[0]);
-		totals[1] = add_int64(totals[1], times[1]);
-		totals[2] = add_int64(totals[2], times[2]);
-		totals[3] = add_int64(totals[3], times[3]);
-		totals[4] = add_int64(totals[4], times[4]);
-		totals[5] = add_int64(totals[5], times[5]);
-		totals[6] = add_int64(totals[6], times[6]);
-	}
-	*/
 }
 
 // Resets the times of the provided task (and adjusts database totals).
@@ -1340,19 +1246,6 @@ int main(int argc, char *argv[]) {
 	
 	load_database(&database, db_file_path);
 	
-	// TODO WIP WIP
-	clock_t start = clock() ;
-	update_total_times(&database);
-	clock_t end = clock() ;
-	double time_sec = (end-start) / (double)CLOCKS_PER_SEC;
-	double speed = (double)database.count / (1000000.0 * time_sec);
-	double usPM = 1000000.0 * 1000.0 * time_sec / (double)database.count;
-	endwin();
-	fprintf(stderr, "update of %zd took: %9.3fms\n", database.count, time_sec);
-	fprintf(stderr, "speed: %9.3f MOPS\n", speed);
-	fprintf(stderr, "tpm  : %9.3f usPM\n", usPM);
-	return EXIT_FAILURE;
-	
 	flushinp();
 	ungetch(KEY_RESIZE);
 	for (int key; ((key = getch()) != 'q') && (key != 'Q'); ) {